Diminished band discontinuity at the p/i interface of narrow-gap a-SiGe:H solar cell by hydrogenated amorphous silicon oxide buffer layer

The recent research and developments of a-Si:H based solar cells have greatly promoted its position as low cost solar cell. Unfortunately, a-Si:H solar cells suffer appreciable light induced degradation for thickness greater than 200nm. It has been reported that boron doped hydrogenated amorphous silicon oxide (p-a-SiOx:H) films have a low temperature coefficient compared to those based on hydrogenated amorphous silicon (p-a-Si:H) . Moreover, the solar cells with a p-a-SiOx: H generate more electricity than the solar cells with p-a-Si: H window layer due to the wider band gap (Eg) of these films. We present in this paper a computer simulation on the effects of window layer thickness on the performances of single junction amorphous silicon oxide solar cells. We varied the thickness of the window layer from 5 nm to 25 nm and our simulation results showed that cells parameters are significantly affected window layer thickness. However, the film thickness of the p-a-SiOx:H window layer increased from 5 nm to 25 nm, the power conversion efficiency (PCE) of the solar cells respectively decreased in the ranges of 5.733% to 5.271% .the simulation data are in good agreement with the literature

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Numerical Design of Ultrathin Hydrogenated Amorphous Silicon-Based Solar Cell

International Journal of Photoenergy ◽

10.1155/2021/7506837 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

F. X. Abomo Abega ◽

A. Teyou Ngoupo ◽

J. M. B. Ndjaka

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Amorphous Silicon ◽

Buffer Layer ◽

Defect Density ◽

Hydrogenated Amorphous Silicon ◽

Theoretical Work ◽

Silicon Based ◽

The Impact ◽

Hydrogenated Amorphous

Numerical modelling is used to confirm experimental and theoretical work. The aim of this work is to present how to simulate ultrathin hydrogenated amorphous silicon- (a-Si:H-) based solar cells with a ITO BRL in their architectures. The results obtained in this study come from SCAPS-1D software. In the first step, the comparison between the J-V characteristics of simulation and experiment of the ultrathin a-Si:H-based solar cell is in agreement. Secondly, to explore the impact of certain properties of the solar cell, investigations focus on the study of the influence of the intrinsic layer and the buffer layer/absorber interface on the electrical parameters ( J SC , V OC , FF, and η ). The increase of the intrinsic layer thickness improves performance, while the bulk defect density of the intrinsic layer and the surface defect density of the buffer layer/ i -(a-Si:H) interface, respectively, in the ranges [109 cm-3, 1015 cm-3] and [1010 cm-2, 5 × 10 13 cm-2], do not affect the performance of the ultrathin a-Si:H-based solar cell. Analysis also shows that with approximately 1 μm thickness of the intrinsic layer, the optimum conversion efficiency is 12.71% ( J SC = 18.95 mA · c m − 2 , V OC = 0.973 V , and FF = 68.95 % ). This work presents a contribution to improving the performance of a-Si-based solar cells.

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